Decorrelating rake receiver apparatus and method

Abstract

A decorrelating rake receiver (401) using a signal processor (213) and corresponding method (1000) to determine filter coefficients (1005). The decorrelating rake receiver includes a plurality of filters (219) arranged to be coupled to an input signal (403) and the filter coefficients (409), the plurality of filters operable to provide a plurality of output signals and a coefficient generator (407), coupled to the input signal, to explicitly and definitely determine the filter coefficients for the plurality of filters such that the plurality of filters perform a decorrelating rake process. The decorrelating rake receiver further includes a combiner (221) to combine the plurality of output signals and provide a received signal (405). The decorrelating rake receiver (401) is suitable for use in a wireless communication device (101) or base transceiver (103).

Description

FIELD OF THE INVENTION[0001]This invention relates in general to wireless communications devices and more specifically to apparatus and method for facilitating decorrelating rake receivers in such devices.BACKGROUND OF THE INVENTION[0002]Wireless communication devices or units such as subscriber devices and base transceivers providing data and voice services for users operating in corresponding systems are known. As these systems have evolved more sophisticated encoding and modulation schemes are being employed. Present systems often rely at least in part on schemes where orthogonality between signals is utilized to distinguish a signal from all others. A classic example of such a system is a spread spectrum system, such as a code division multiple access system where spreading codes that are orthogonal to each other are used to distinguish one signal from another. In theory when the proper code is used to despread the signal, the desired signal will exhibit a strong positive correl...

AI Technical Summary

Benefits of technology

The present invention relates to wireless communication devices and systems, and more particularly to a method and apparatus for using a decorrelating rake receiver in such devices. The invention provides a way to increase system capacity and reduce multiple access interference (MAI) in wireless communication systems. The invention uses a decorrelating rake receiver that is efficient, deterministic, and predetermined in its approach. The invention can be implemented in special purpose hardware or software and can be used in various communication devices and systems, such as cellular phones, personal digital assistants, and computers equipped for wireless operation. The invention is particularly useful in communication systems that use spread spectrum access technologies, such as CDMA, W-LAN, and Bluetooth. Overall, the invention provides a better way to improve system performance and capacity in wireless communication systems.

Problems solved by technology

However known approaches for implementing decorrelating rake receivers are computationally intensive and typically rely on estimation techniques with unknown convergence properties for estimating parameters.

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